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US4472672A
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High power factor switching-type battery charger
Assignee: Cosden Technology Inc
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Filing: 1982-12-13
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Granted: 1984-09-18
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Expires: 2002-12-13
Abstract
Abstract A switching-type charging circuit is described wherein the power factor of the circuit has been optimized. The switching-type charging circuit utilizes a dual loop feedback system to control the input and output current of the circuit. The dual feedback loop system utilizes a sinusoidal voltage reference in conjunction with a pulse width modulation circuit to force the input impedance of the circuit to appear substantially purely resistive.
Inventors
- 👤 David R. Pacholok
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:40
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/42; H02M1/4208; H02J; H02J7/00; H02J7/02; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; H02M3/1563; H02J2207/00; H02J2207/20; H02M1/4291; Y; Y02; Y02B; Y02B40/00; Y02B70/00; Y02B70/10; Y10; Y10S; Y10S320/00; Y10S320/22
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
131 words
An improved switching-type charging circuit operated from an AC power source for charging a battery wherein the operating power factor is optimized and further wherein the charging circuit includes a pulse width modulation circuit controlling a switching transistor together with a current sensing means, said charging circuit including in combination: an electronically variable sinusoidal voltage reference means coupled to the AC input means; a D.C. voltage reference means for generating a reference voltage related to the battery voltage and temperature; a first feedback loop responsive to said current sensing means and said D.C. voltage reference means for controlling said electronically variable sinusoidal voltage reference means; and a second feedback loop means responsive to said current sense means and said electronically variable voltage reference means for controlling said pulse width modulation circuit.
Claim 2
Dependent Claim
131 words
An improved switching-type charging circuit operated from an AC power source for charging a battery wherein the operating power factor is optimized and further wherein the charging circuit includes a pulse width modulation circuit controlling a switching transistor together with a current sensing means, said charging circuit including in combination: an electronically variable sinusoidal voltage reference means coupled to the AC input means; a D.C. voltage reference means for generating a reference voltage related to the battery voltage and temperature; a first feedback loop responsive to said current sensing means and said D.C. voltage reference means for controlling said electronically variable sinusoidal voltage reference means; and a second feedback loop means responsive to said current sense means and said electronically variable voltage reference means for controlling said pulse width modulation circuit.
Claim 3
Independent Claim
116 words
A method for optimizing power factor when using a switching-type power supply operating from an AC power source, for charging a battery, and having a pulse width modulation circuit controlling a switching transistor together with a current sensing means, including in combination: deriving an electronically-variable sinusoidal voltage reference from the AC input means; generating a DC voltage reference related to the battery voltage and temperature; utilizing a first feedback loop responsive to said DC voltage reference and said current sensing means to control said electronically variable sinusoidal voltage reference means; and utilizing a second feedback loop, responsive to said current sense means and said electronically variable voltage reference means to control said pulse width modulation circuit.
Claim 4
Independent Claim
116 words
A method for optimizing power factor when using a switching-type power supply operating from an AC power source, for charging a battery, and having a pulse width modulation circuit controlling a switching transistor together with a current sensing means, including in combination: deriving an electronically-variable sinusoidal voltage reference from the AC input means; generating a DC voltage reference related to the battery voltage and temperature; utilizing a first feedback loop responsive to said DC voltage reference and said current sensing means to control said electronically variable sinusoidal voltage reference means; and utilizing a second feedback loop, responsive to said current sense means and said electronically variable voltage reference means to control said pulse width modulation circuit.
Claim 5
Dependent Claim
16 words
The circuit of claim 1 wherein said current sense means includes resistor and an operational amplifier.
Claim 6
Dependent Claim
20 words
The circuit of claim 1 wherein said electronically variable sinusoidal voltage reference includes a transformer, a resistor and an opto-isolator.
Claim 7
Dependent Claim
20 words
The circuit of claim 1 wherein said pulse-width modulation circuit includes a ramp generator, a comparator and an error amplifier.
Claim 8
Dependent Claim
24 words
The circuit of claim 1 wherein the DC voltage reference includes an operational amplifier, a thermistor, a zener diode and a resistor divider network.
Claim 9
Dependent Claim
18 words
The circuit of claim 1 wherein the DC voltage reference is optically isolated from the first feedback loop.
References Cited (Backward Citations)
US3068392A
Cited
US3419792A
Cited
US3629681A
Cited
US3731183A
Cited
US3876921A
Cited
US3821635A
Cited
US4087733A
Cited
US4160945A
Cited
US4242627A
Cited
US4321523A
Cited
US4339705A
Cited
US4384321A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |